SR: BRCA mutations are not associated with colorectal cancer

Reference

Cullinane CM, Creavin B, O'Connell EP, et al. Risk of colorectal cancer associated with BRCA1 and/or BRCA2 mutation carriers: systematic review and meta-analysis. Br J Surg 2020;107(8):951-959.

Synopsis

These authors searched several databases to identify studies that explored the association between BRCA mutations and CRC. The authors don't describe the process of article selection or if the quality of studies were assessed independently by multiple authors. The authors anticipated specific BRCA mutations, age, sex, and Ashkenazi Jewish heritage as possible sources of heterogeneity and performed subgroup analyses. They included 11 studies of patients with confirmed BRCA1 or BRCA2 mutations: 7 cohort and 4 case-control studies. Only one of the studies was prospective. The individual studies were at low to moderate risk of bias. The studies included 14,252 participants, among whom 4831 cancers were detected. Since 5 of the studies only included Ashkenazi Jews, this group represented the majority of the patients. The authors found no association between any BRCA mutation and incident CRC (odds ratio [OR] 1.03; 95% CI 0.80 - 1.32). They identified a trend toward a modest increased risk with BRCA1 mutation carriers and CRC, but this was not statistically significant (OR 1.27; 0.91 - 1.76). Among patients with BRCA2 mutations, there was no increased risk of CRC (OR 1.10; 0.71 - 1.69). When adjusting for age, sex, or Ashkenazi Jewish descent, the relationships did not change. The authors found no statistical heterogeneity and no graphic evidence for publication bias.